Method of building foundations for subaqueous tunnels.



D. D. McBEAN.

METHOD OF BUILDING FOUNDATiONS FOR SUBAQUEOUS TUNNELS.

APPLICATION FILED SEPT- |3 l lfi 1 ,272,479. Patented Julyl6, 1918.

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METHOD OF BUILDING FOUNDATIONS FOR SUBAOUEOUS TUNNELS.

APPLICATION FILED SEPT. I3, I9lfi.

1 372,479. Patented July 16, 1918.

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METHOD OF BUILDING FUUNDATIONS FOR SUBAUUEUUS TUNNELS.

APPLICATION FILED SEPT- !3, 19m.

1 ,272,479. Patented July 16, 1918.

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DUNCAN D. MOBEAN, OF NEW YORK, N. Y.

METHOD OF BUILDING FOUNDATIONS FOR SUBAQUEOUS TUNNELS.

Specification of Letters Patent.

Patented July 16, 1918.

Original application filed February 21, 1916, Serial No. 79,594. Divided and this application filed September 18, 1916. Serial No. 119,802.

To all whom it may concern:

Be it known that I, DUNGAN D. MOBEAN, a citizen of the United States, residing at New York, in the county and State of New York, have invented certain new and useful Improvements in Methods of Building Foundations for Subaqueous Tunnels, of which the following is a full, clear, and exact description.

This invention is an improvement in the methods of preparing the foundations for subaqueous tunnels, dock walls and piers and for deepening river and channel beds, and is designed with special reference to a saving in the amount of labor and expense involved in such work. This application is filed as a division of an application No. 79,594, filed by me on February 21st, 1916, and patented March 26, 1918, No. 1,260,416.

I have heretofore devised and patented methods and means for constructing tunnels, more fully set forth in Letters Patent Nos. 745,454; 745,456; and 745,457, dated December l, 1903; and Nos. 797,524 and 797,525, dated August 15, 1905, in which, as a definite feature characteristic to all, revision was made for the buildin of a xed working chamber 011 the site 0 each tunnel section. In other words, the plan in general was first to dredge out as far as convenient or practicable, the space in which the work is to be done, to then construct around and inclosing the space in which the structure is to be built, a working chamber, practically water and air tight, to then ump the water out of such chamber, replacing 1t with air under suflicient pressure to equalize the load of superincumbent water, and to carry on the work of tunnel construction within this fixed working chamber. The several patents mentioned above cover this general method and certain detailed improvements upon the same.

In all of these methods and inventions the tunnel foundations were prepared by driving piles into the bottom or site and cutting them off with appliances working from above the surface of the water.

Numerous patents have been granted and plans proposed for buildin tunnels or sections of the same at the sur' ace of the water and lowering them into a trench dredged out from the bed of a river or other body of water, but none of them have disclosed a practicable form of movable chamber or any device of that nature for unwatering the site in which is to be prepared a foundation for the support of the tunnel in advance of sections thereof lowered upon the bed of the trench, and these are only some of the objections which are present in the usual methods of subaqueous tunnel construction. Other objections, however, exist in such cases, mainly in that there has always been required a fixed working chamber or caisson for each length of tunnel and that the tunnel proper must be built within a subaqueous working chamber, instead of being com pleted or nearly so, at the surface and then lowered into place.

lVith a view to obviating these and other difliculties, and more especially as an improvement on the methods set forth in my several patents above enumerated, I have devised a plan for carrying on such work that presents many and distinct advantages. According to my present invention, I proceed as follows:

I build what may be termed a. submarine locomotive working chamber or dredge, that is to say, an open bottom compressed air chamber formin the lower portion of a sub-- marine vessel, w ich has water ballast tanks in its upper part, and which is provided with suitable means and appliances for raising and lowering the vessel in the water. The device is referably equipped with pipes extending rom the air chamber through the vessel and overlying water to air locks above the surface of the body of water.

This vessel is lowered onto the bottom of a body of Water and utilized to excavate a trench or to sink into a previously dredged one and is adapted to travel horizontally on the river bed or trench bottom, preferably on rails laid temporarily on the tunnel foundations as they are progressively built. The compressed air chamber is preferably equipped with machinery and appliances of suitable character for preparing the tunnel foundations and movin the vessel forward or backward as these foundations are put under it.

The bottom of the structure constituting the working chamber, is open and forms a chamber in which the proper air pressure may be maintained to exclude the water and to permit workmen to carry on the necessary operations involved in preparing subaqueous foundations or deepening river and channel beds. Through the entire structure from top to bottom or alongside of the same, there may be provided suitable guide-tubes or passageways through which piles or sheeting may be driven from the surface, and in the compressed air chamber, circular or other saws may be placed and adjustably mounted on supports therein, to cut off these piles or sheeting at the exact levels desired, and this without reference to the exact location of the piles with reference to the structure above it, or whether said piles have been driven through the tubes in the struc ture or outside of it. In the case of a rock bottom the latter may be excavated and raded and cement columns or sup orts may lie laid upon it of the proper heiglit so that in either case the preparation of a foundation at any exact and predetermined grade and alinement for tunnels in sections of any length is greatly facilitated.

The workingchambermay be equipped with a dredglng plant the suction pipes passing through the vertical walls and baittom of the structure. These pipes may e pivoted when so desired, and means may be employed for adjusting the position of the same when pivoted, controllable, preferably, within the compressed air chamber, which pipes communicate with suitable pum s within the air chamber, whereby mud, silt or other soft material from the sides, bottom and ends of the trench in which the structure is working may be removed by the pipes and raised to scows on the surface. In this way any material which may cave from the sides or ends of the trench, or any silt that may flow into it, may be removed, thereby insuring the structure from eing buried or blocked in its motion horizontally on its tracks by material collecting in the trench about it, and the structure maylower itself to a depth greater than its height by excavating under it, through freeing itself from skin friction on its sides and ends, by pumping out suflicient of the material exterior to it, and thus the structure is enabled to run back on its temporary tracks and clean off any debris, mud or silt that may have collected on the finished foundation behind it, and the temporary tracks may thus be removed in advance of a tunnel section bein lowered thereon The tracks upon which the structure may run may be laid on the bottom or on a reviously repared foundation, and may e extende to any distance.

The structure is preferably arranged with devices between it and the tracks to permititiabove the latter to a height sufli} raisin for 1t t r fly aubles 9. ether 6} cient stacles in its path, or, in cases where the foundation is to be built on an inclined rade, to permitthe raising and holding of tie vessel in position, so that the bottom of the Working chamber will be level while it is traveling thereon, or while work on an inclined grade is being done under it. For this reason it is preferable to provide means on the trul'zks on which the structure rests for raising or lowering one or both ends of the same.

Another pur ose in raising and lowering the structure is in the fact tl at it will be advantageous to raise it a few inches to permit the cutt ng off of the piles or sheeting, especially those driven outside of the structure, in the water a few inches below its surface in the working chamber, and then after they are cut oil to lower the structure again and to increase the air pressure Within the working chamber sufficiently to lower the surface of the water under it below the top of the cut off piles or sheeting. This enables the workmen to cap the piles, to test them for levels or to excavate the material inelosed by the sheetin or to otherwise prepare the foundation aiout the piles and to brace them in case the foundation which they provide is above the water bed,

The strueture may be run forward or backward over the rails as may be necessary so that a foundation for a tunnel may 'be built in full view, in air, instead of being constructed under water, or by means of fixed working chambers.

These and other results which are secured by my invention tend to very greatly reduce the cost of tunnel construction and very materially lessen the labor and difficulty experienced in such work. In addition to providing a cheap and ready means of laying tunnel sections, lowered successively to their final s ee in the ordi y ay, nvention aflords a means for carrying out other and entirely new processes of constructing tunnels, as by building up their sections While'they are fleating in an up right position in the water, and then tipping them onto a substantially horizontal foundation, an invention w lCll is not further herein described, as it as been madethe j c f oth r epp ieet ens- Referring now to the drawings hereto aunexed, which illustrate the manner above outlined of carrying out the inventipn Figure 1 is a sectional view of what I have e e e is a ym submarine l em ham ere d dge a ructure th en al character and dimensiohs ofa section of a un e a d a gen r y of semewh rea r e's h han Wid h n t is figure the section is along'the l ne of the greater dimension. d i

ie- 2, s a. e sonal ew oi the tru ture lying over a foundation prepared in a rock trench.

Fig. 3 is a sectional view of the same struc ture equipped with dred ing and other appliances and means or driving piles through the structure.

Fig. 4 is a similar view of the same parts, showing the means employed for advancing it along a previously excavated trench.

Fig. 5 is a somewhat enlarged view, illustrating more in detail the passageways through which piles are driven.

Fig. 6 is a sectional view showin the use of sheet piling in the preparation 0 a foundation for a sub-aqueous structure.

Fig. 7 is a sectional view illustrating the manner of carrying out the excavation of a trench and preparing a foundation in a man ner permitted by the use of this invention,

Fig. 8 is a plan view showing a sheeting piling passage way at the top of the structure.

The general construction of the submarine excavating dredge is shown in Figs. L and 2. This consists of a box-like structure, provided at the top with closed compartments which serve as water ballast chambers, at the bottom with an open bottom chamber 2, and built in any proper and substantial manner with I-beams 4 at the top and bottom and beams 5 to support the partition 6 between the two or the upper and lower com partments. A tube 7, provided with the usual air locks for entrance into and egress from the compressed air chamber, may pass down through the structure vertically from the surface and opens into the lower compressed air compartment 2. This tube has a joint formed by flanges 47 secured together by bolts or other means which may be quickly and easily removed by a diver.

Extending down through the structure at proper points are a series of tubes 12 to serve as guides for piles, which may be introduced through them and driven into the material of the water bed from the surface. Similar guiding passages may be attached to the outside walls of the structure, if so desired, such as are commonly used for spuds in structures of this kind, as shown at 12 in Figs. 2 and 6. When desired there may also be provided elongated openings 3 through which sheet piling may be driven so as to form a continuous air and water tight wall around the site of a submarine structure, so

, that when the ends of the sheeting project up into the compressed air within the working chamber, the material within the sheeting walls may be readily excavated to the depth requisite for the foundation of the structure to be placed thereon. The tubes 12, and 3, where they enter the compressed air compartment 2, have joints by means of which their lower ends may be removed after the piles are cut off, and valves 15 are provided above such joints which may be closed when the lower ends of the tubes are detached.

As a further illustration of the appliances used with the structure, reference is made to Figs. 3 and 4. Upon the lower cross beams a suitable platforms are provided upon which is mounted a compressor 16, which receives the requisite free air from the surface through pipe 17, and a pump or pumps 18 connected to a pipe 19 running up to the surface or other convenient point, where it is suitably bent over to discharge into a scow 20. From the pump 18 leads a horizontal pipe 21, extending out in branches through the vertical side walls and below the bottom inside of the structure and connecting with suction pipes 2 pivotally connected thereto outside the vertical walls. It will be understood that there may be as many pumps 18 as are necessary and any suitable number or arrangements of valve controlled suction pipes to work on any or all sides of or beneath the bottom of the structure.

The position of the pivoted suction pipes 24, which are not accessible from within the chamber, may be controlled by any suitable means. For this purpose I have shown these pipes supported by ropes 25 running over pulleys 26 and carried through comparatively tight openings in the walls of chamber 2 within which they are wound upon a reel 2 Any suitable means other than this may be employed to adjust the position of pipes 24 from within the chamber, or otherwise.

In the compressed air chamber 2 is also a motor 32 which is removably supported on the beams 4, and which drives by suitable beveled gearing a vertical shaft carrying a circular saw Any suitable device may be employed to this saw, the purpose of which is to out ofl? at any requisite level to which it may be adjust-ed, the piles or sheeting 13. It is intended that the saw shall be moved to the ends or sides of the structure and adjusted to cut off below the lower cutting edge of the working chamber piles or sheet piling that may be driven outside of the structure.

When the structure is used for preparing foundations or for submarine dredging by the operation of the devices above described, it is desirable that it should be movable along a predetermined level, and for this purpose I lay caps along the tops of the sawed off piles and run trucks upon rails 34 laid thereon. The cross beams 4 rest upon these trucks, and the whole structure is thus supported upon the trucks. Any means, such as blocks or tackle 37, controlled either from within or without the chamber 2, may be employed to advance the structure as oocasion may require, or it may be drawn back by a tackle 38.

perform the functions of The structure may be raised or lowered with respect to these trucks by jacks 39 placed between the trucks and beams 36 se cured to the upper side of beams 4, thus proriding for an elevation or depression of the structure for carrying out its intended functions, or for passing over obstacles encountered by it, and enables the bottom of the compressed air chamber to be kept on a. level when the structure is traveling on an ascending or descending grade,

hen the bottom is rock and the depth to be excavated is too great for it to be done in one cutting, the length oft-ho locomo tive structure is made somewhat. greater than the width of the trench neci-issary for the tunnel structure. The structure is then placed lengthwise aciross the site of the trench, and the first cutting is made of a somewhat greater width than that required for the tunnel structure. After the first cutting is excavated the structure is then turned at right angles and lowered into the first cutline when the trench is deepened lo the depth required for the foundation of the tunnel. The proceeding followed in preparing the foundation is that bases or columns of concrete 40 are laid upon the rock bottom and are given the required height to form a proper foundation, as shown in Fig. 2. Y

In Figs. 6 to, 8 Ivhave illustrated a plan of preparing foundations in trenches in the bed of a body of water which may be carried out by means of this invention. According to this plan a. trench may be eXcavated in the river bed by an ordinary dredging machine or any other means, and carried down to within a few feet of the depth intended for the foundation. In this trench the submarine vessel may rest upon temporary tracks laid on planks or cross beams and brought up to the point where the dredged. trench of less than the required depth begins. The vessel is then raised by the jacks upon its trucks until its forward bottom edge is above the level of the cxcw voted trench, and it is then forced forward for a certain distance over the latter.

The excavation down to the level desired for the foundation is then completed by the appliances carried by the submarine vessel. In the meantime, as the vessel is advanced, piles are or may be driven down through it, and either during its progress or on its return movement, in case the piles have been driven at its rear, these piles are cut off at the proper level and utilized as a foundation, or, if need be, for the rails on which the trucks travel. In all cases the material underlying the structure is substantially unwatered by the air pressure in the chamber.

Any means known in the art may be utilized for lowering sections of a tunnel onto the foundation prepared for them in a trench as above described.

15v means of this invention, I may lay tunnels of any cross section or shape and I may also prepare the foundations for piers, (lock walls and the like.

\Vliat 1 claim as my invention is:

1. The method of preparing foundations for subauueous structures herein described, which consists in lowering to the bottom of a. river or other body of water a submarine locomotive structure having at its lower portion an open bottom compressed air chamber, unwatering the part of the site under the structure, dredging progressively a length of trench under the same, prcparinn therein a foundation at the proper level, re moving the structure from the prepared foundation and lowering thereon the structure intended for such foundation.

2. The method of building foundations for subaqueons tunnels and the like placed thereon, which has been herein described. which consists in lowering to the bottom of a river or other body of water a submarine locomotive structure having at its .lmverportion an open bottom. compressed air chainber, unwatering the. site of the foundation under the structure, excavating by suitable appliances contained. in said chamber, progressively a length of trench, driving piles through passages extemling from the top to the bottom of the structure to form a foundation in the trench, and then lowering thereon the tunnel or other structure intended therefor.

33. The method of preparing foundations for aubaqueous tunnels and the like placed thereon, which has been hereinbcfore described, which consists in lowering to the bottom of the river or other body of water a. submarine locomotive structure having in its lower portion an open bottom com pressed air chamber, unwatering the site of the tunncl under the structure, excavating by suitable appliances contained in said chamber, progressively, a length of trench driving piles in the bottom of the trench through passages extending from the top to the bottom of the structure and cutting them off at the proper levels to form a length of foundation in the trench, and then lowering thereon the tunnel sections intended therefor.

4. The method of building foundations for subaqueous tunnels placed thereon, herein described, which consists in lowering to thebottom of a body of Water a submarine locomotive structure having at its lower portion an open bottom compressed air chamber, unwatering the site of the tunnel foundation under the structure, excavating by appliances contained in said chamber. a tunnel trench under the structure, driving piles in the bottom of the trench, cutting them off at the desired levels, laying tracks thereon and advancing the structure by trucks running thereon to progressively unwater and prepare lengths of foundation in proper alinement for tunnel sections to he lowered and laid thereon.

5. The method of building foundations for laying thereon subaqueous tunnel sections herein described, which consists in lowering a submarine locomotive structure having its lower portion formed as an open bottom compressed air working chamber and having one dimension greater than the width of the proposed tunnel, placing said structure lengthwise across the line of the proposed trench, unwatering the water bed under the structure, excavating under the said structure by appliances contained in the working chamber the trench to the required depth, then turning the structure at right angles and lowering it into the cut thus made, and then preparing the foundation for the subaqueous tunnel under same.

6. The method of building foundations for subaqueous tunnel sections placed there on, which consists in lowering to the bottom of a body of Water a submarine locomotive structure having in its lower portion an open bottom compressed air workingchamber, dredging by pipes leading through its walls into the compressed air chamber the material from about the structure to form a trench, raising the said material from the chamber to the surface and preparing a foundation in the trench through the open bottom of the compressed air chamber and then lowering and laying a section of the tunnel thereon.

7. The method of progressively prepar ing foundations for subaqueous tunnels, which consists in lowering to the bottom of a body of water a submarine locomotive structure having in its lower portion an open bottom compressed air chamber, excavating a trench under the structure, reparing a foundation in the trench and a vancing the structure by trucks running on rails laid upon said foundation.

8. The method of pro re'ssively preparing foundations for 'suiaqueous tunnels herein described, which consists in lowering to the bottom of a body of water a submarine structure having at its lower portion an open bottom compressed air chamber, excavating under the structure a tunnel trench, preparing therein a foundation, laying, rails upon said foundation, and moving the structure on the same by trucks and raising or lowering the structure with respect to the l same.

'9. The method of preparing foundations for "a subaquedusf tunnelffinja trench. in the bottom of a body of water, which 'consists in lowering to the bottom a submarine structure having an open bottom compressed air working chamber under it, advancing the structure on tracks laid in the trench, preparing n-ogressively by appliances contained in the working chamber, a foundation in the bottom of the trench and lowering and laying tunnel sections thereon.

if). The method of preparing foundations for subaqueous structures which consists in lowering to the bottom of a body of water a submarine structure having in its lower part an open bottom compressed air working chamber, unwatering the bed under the structure, driving progressively sheet piling through passages in the structure around the intended site, and excavating the material between the walls of the sheet piling to the required depth for the foundation for the structure intended therefor.

11. The method of preparing foundations for subaqueous structures, which consists in lowering into a trench dredged in. a water bed, a submarine structure having in its lower part an open bottom compressed air Working chamber, unwatering the bottom of the trench under the structure, driving sheet piling through passages in the structure into the material underlying the structure and around the site of the subaqueous structure, excavating material be tween the walls of the sheet piling to the depth required and building the foundation thereon.

12. The method of preparing foundations for subaqueous structures, which consists in lowering onto the bottom of an overlying body of water, a submarine locomotlve ve s sel having an open bottom compressed air Working chamber, univatering the water bed under the vessel by the air pressure in the Working chamber, driving through passages in the vessel sheet piling in the material under the same around the site of the sub aqueous structure, cutting off the piling by appliances within the working chamber slightly below the surface of the water therein, then lowering the vessel to bring the tops of the sheeting above the water level within the chamber, excavating the material between the Walls of the sheeting to the re,- quired depth for the foundation laying on the foundation prepared under the vessel the section of the tunnel then advancing the vessel progressively over ad acent lengths of the site of the subaqueous structure and cutting out the sheet pilin and walls as the structure is built in their p ace.

13. The method of building foundations for subaqueous tunnels, which consists in lowerin onto the site of the tunnel a sub marine ocomotive structure having an open bottom, forming a compressed a1r working chamber, unwatering the tunnel site under the structure, dredging in advance of the structure the materlal overlying the tunnel site, driving piles in the material of the site, cutting them off nogressively as the structure advances, by appliances in the com pressed air chamber, laying thereon tom porary tracks For trucks for carrying the structure and preparing under the structure as-it advances a foundation for successive sections of the tunnel.

14. The method of preparing foundations for a subaqueous tunnel, which consists in lowering onto a track laid in a trench dredged in the water bed, a submarine locomotive structure having an open bottom forming a compressed air working chamber, unwatering the tunnel site under the structure and preparing progressively lengths of foundation to receive tunnel sections lowered thereon.

15. The method of preparing foundations for a structure whose base is below the surface of the body of water, which consists in maintaining on supports placed on the water bed, a submarine locomotive structure having an open bottom and forming a compressed air working chamber, unwa tering lengths at the required depth of the site under the structure and preparing progressively by appliances contained in'the Working chamber lengths of foundation for the structure to be lowered thereon.

16. The method of preparing foundations for receiving subaqueous tunnel sections, which consists in supporting on trucks traveling horizontally on a prepared foundation in the Water bed, a submarine structure haw ing in its lower portion an open bottom compressed air working chamber, unwatering the tunnel site under the structure, dredging out the material from under and about the structure through the working chamber to the desired width and depth and preparing under the Working chamber and through its open bottom a foundation for the sections of tunnel to be laid thereon.

'17. The method of preparing foundations for receiving sections of asubaqueous tunnel, which consists in supporting upon trucks running on tracks laid on the tunnel site a submarine structure having at its lower end an 0 en bottom compressed air working cham er, unwatering the tunnel site under the structure, excavating the said'site to the required Width and de 'th, preparinga foundafiion under the wor 'ing chamber, movi'n' the structureahead overthe tunnel site an leaving int'he'rear the foundation for the sections of tunnel;

18.- The methoddf'preparing foundations for subaqueous tunnel sections, which consists in lo'weringon to-the water'bed a sub marble leeemotive structure having at its Dewerendan compressed air chamber, unwater ing the water bed under the structure, removing the water bed material under and around it sufliciently toenable it to sink freely to the required depth, by pipes leading into the (xnnpressed air chamber from outside of the structure and preparing pmgressively under the working chamber a foundation for the sections ct tunnel.

19. The method of building foundations for a subaqueous tunnel, which consists in supportin in a trench prepared in a water bed, a suimarine structure having at its lower end an open bottom com ressed air chamber, removing the material rom under and around the structure into the conr pressed air chamber and sending it to the surface through tubes provided therefor, unwatering the tunnel site under the structure and preparing a foundation thereon to receive the tunnel sections as the structure is advanced.

20. The method of preparing foundations for subaqueous tunnel sections on an inclined grade, which consists in advancing in a prepared trench on trucks running on rails, a submarine structure having at its lower end an open bottom compressed air working chamber, adjusting the structure with respect'to the rails so that its bottom is level, unw tering the tunnel site under the structure a 'pre aring thereon the foundation for receiving. he tunnel-sections.

21. The method of buildin foundations for subaqueous tunnels, whic' consists in supporting in a prepared trench in the Water bed, a submarine locomotive structure, unwatering the trench under the structure, driving piles from the surface of the water through passages in the structure, sawing off the piles at the required level Within the structure and preparm bymeans of such piles the foundation r sections of the tunnel 2'2. The method of building foundations for sub, ueol ls tunnel sections, which e0nsist's in. amtrench in the bed of a body'ofi Water toadeptlt somewhat lessthan that required for the foundation; advancing in such trenchby travelingsupportsra subrratij tnelocomotivestructurehm open b tto compressedair chamber'un eriannateng and excavating t e trench under thesttfucture therequi depthandiprep li lgfi bll ldatibnr thereon. 0 receive tunnelsec ions asthe structure a var ces.

1 the methedof; paringioandations prgs baqa ,ous, tunne sections, which conse s, a earch m a ench dre ge in the li -Winni t tlr', a s b crime locomotiveistructifi're lavi'ngan open" ottpm, oomresse aircam ertun der it .u teresteemsaiigasamnlfii 3 rrdra ng. m. .b tit lis thereoii, laying;

tracks upon such foundation for trucks to support and advance the structure and removing such trucks to leave the foundations: in the rear of the structure in condition to receive the sections of tunnel.

24;. The method of deepening beds of rivers and other bodies of water, which consists in lowering onto the bet] a submarine locomotive structure having under it an open 10 bottom compressed air Working chamber, ad-

vztneing the structure on supports on the material of the water bed, unwatering the bed under the structure and removing the materinl therefron'l into the working chamber and removing the same from said chamber to the surij'acc.

In testimony whereof ,l, hereunto afl'ix my fii gnatture.

DUNCA N I). MoBEA N.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

